1. Field of Invention
The present invention generally relates to a type of immobilization weapon which impart high-tension electricity to disable and capture, and more particularly to such a type of weapon which employs at least one cartridge for launching two tailing-wired spreading apart electrical projectiles, to impact a living target and to discharge said high-tension electricity between the two points of the projectiles. The present invention provides improvement over the prior art to significantly increase the effectiveness and accuracy of such weapons.
2. Prior Arts
Weapons for immobilization and capture are generally referred to as “Stun guns”. Such devices basically consist of a launch section and a body section, of which the launch section normally contains at least one single cartridge apparatus while the body section mainly accommodates the stun gun electronics and battery compartment. The electronic circuits of the weapon's power supply normally comprise one internal open circuit which, upon its closure, charge the electricity from the battery into the capacitor; and one external open circuit defined by a pair of narrowly spaced electric opposed electrodes on the weapon which, upon firing, is mechanically extended through the conductive wires to a remote target. In practice, the weapon projects two spreading-apart projectiles tethered by the conductive wires with a high voltage difference in between. Immobilization occurs when the space between the projectiles is filled with a living target and the electrical impulses pass from one projectile to the other to complete an electric circuit, dumping electricity into the target's neuromuscular system.
The effectiveness of such weapon depends, among other thing, on its power output and the distance between the projectiles when they are in contact with the target. When said power output is defined, the spreading of the projectiles will largely determine the weapon's efficiency. Within a certain range, the wider the spread between the projectiles, the more extensive the tissue involved for electrical neuromuscular interference, and the more intense the weapon's immobilization ability. However, the increase in spreading for improved effectiveness is not without limit. With the increased spreading, the path for completing the weapon's return circuit also increases, which would involve more tissues of different types of which the linkage of the biological and bioelectrical properties become weaker between tissues. For example, a space between the projectiles greater than 25 inches would not only increase the risk of the projectiles missing the target but also would be likely to reduce its incapacitating efficiency. In order for the electrical impulses to sufficiently disable a human target, the minimum space between two contactor or projectiles is generally considered to be 5-7 inches as described in U.S. Pat. No. 5,841,622. The physiological response at different spreading distances range from merely pain compliance when the spreading is below the said minimum effective distance, to increased intensity of involuntary muscular contraction with the increase of spreading distances, till total override of central nerve system at which a subject lose the ability to voluntarily overcome the contracting force.
Numerous patents disclosing such weapons have been issued which include U.S. Pat. No. 6,256,916 and No. 5,936,183 to Mc Nulty et al; U.S. Pat. No. 5,786,546 to Simson and U.S. Pat. No. 5,654,867 to Murray.
Weapons disclosed in the prior art were desired to have reliable disabling ability; to be as compact and lightweight as possible; to be easily concealable and to have great accuracy covering both close and long range effectiveness. Such a weapon commercialized under the TASER brand is a good example. The TASER weapon possesses superior incapacitating power; weighs only 175 grams and has a body configuration of 6.0×3.2×1.3 inches. Its cartridge weighs only 2 oz and its sizes is 2.13×1.75×1.38 inches. U.S. Pat. No. 6,256,916; No. 5,654,867 and No. 5,786,546 describe similar cartridge structures and configurations. Owing to the restricted space, the electrical projectiles within the cartridge can only be separated a few millimeters apart (6 mm at the exits for a TASER weapon). As a consequence, the projectiles cannot reach an adequate spacing of at least 5 inches after leaving the cartridge for close range effectiveness. The problem is lessened by placement of the two projectiles as such that they intersect at a small angle, so that they can continue to spread apart after being launched and reach the required minimum spread closer to the weapon. However, the improvement for close range effectiveness is compromised by the reduced long range effectiveness since the excessive spreading will lead the projectiles to miss a more remote target. Thus, the compact configuration of the weapon and the angular arrangement of the projectiles in the prior art result in a relatively limited operational shooting range. Below is a list ranking the differences between the distance from a TASER weapon to a target and the spreading space of the two projectiles.
Spread / Distance ChartDistance To Target (feet)2′ 3′ 5′  7′10′ 12′ 15′ 20′ (1 foot = 30.48 cm)(61 cm)(91 cm)(152 cm)(213 cm)(305 cm)(366 cm)(457 cm)(609 cm)Spread (inches)3″5″8″12″17″20″25″34″(1 inch = 2.54 cm) (8 cm)(13 cm) (20 cm) (31 cm) (43 cm) (51 cm) (64 cm) (86 cm)
As can be noticed, when a target is within a close range of 4 feet to the weapon, the spread of the projectiles would not deliver satisfactory disabling result since the space between the projectiles have not reached the minimum 7 inches, while at a distance longer than 15 feet the projectiles would most likely miss the target because of the excessive spreading of the projectiles relative to a human body or small animal. The optimal shooting range of such a weapon is actually about between 4 feet to 12 feet with maximum accuracy, while closer than 4 feet or longer than 12 feet will likely to cause malfunction. The intersect angle between the projectiles is stated to be 8-12 degrees in such weapons. Further increase of the angle is highly undesirable since it will drastically reduce the long-range effectiveness. The limited effective shooting range of such weapons, both minimum and maximum range, is a serious drawback and could cause dangerous consequences.
It has been found that there exists a range of optimal spreading distance between the projectiles. Within this range, a living target will receive maximum electrical flow and hence achieve maximum effectiveness of a weapon's power supply, which is often characterized by the intensified neuromuscular contraction to such a level at which a subject could not voluntarily overcome the contracting force. While outside this range, both at close and long shooting range, the effectiveness would deteriorate and a subject could gain at least partial mobility while being shocked. For instance, a subject could tear off the insulated copper wires and cause the break down of the weapon's electric circuits as have been observed. To adapt for the changing spreading between the projectiles, the common practices have been to increase the weapons overall power output or prolong its electrical discharge durations or both, which, although would compensate for the deterioration, could result in the electric overload to a subject when the spreading is within the optimal range and render the weapon more dangerous. For a conventional weapon, the said optimal range of spreading often lies in the middle of its effective shooting range, which starts several feet away from the weapon and ends quickly owing to the continued spreading of the projectiles. Therefore, it is deemed desirable to provide a weapon which would reach said minimum effective distance and said range of optimal spreading as close to the weapon as possible and would keep an appropriate spreading distance as far as possible when desired. In such case, instead of defining a weapon's overall power output to adapt for changing spreading distances between the projectiles, the weapon would maintain a constant appropriate projectiles spreading for most of its shooting range, and hence a specific optimized power output can be defined. This would not only reduce a weapon's overall power output to minimize its potential life-threatening hazards while at the same time maintain its maximum effectiveness, but also increase the level of protection for the peace and law enforcement officers who use the weapons.
U.S. Pat. No. 6,575,073 discloses a method and apparatus with the aim to overcome the limited effective range problem. The apparatus in this patent consists of dual vertically spaced-apart cartridges of which each cartridge can launch at least one electrical projectile. Owing to the relative longer spacing and smaller intersect angle between the projectiles, which are 5 to 7 inches and 5 degrees respectively, it can provide an effective shooting range of between 2 and 30 feet. In this case, however, the advantage of relatively improved effective shooting range gives way to a rather bulky body structure. For example, in order to achieve a reasonable result based on the description in this patent, the dual cartridge apparatus would be having a size of approximately 5-7×3-4 inches and a weight of several times that of a standard TASER cartridge. Besides, by using plurality of projectiles and attached wires, the efficiency of the propellant will be reduced, and the increase of total weight of projectiles and wires will also increase the gravitational effect. Furthermore, the plurality of projectiles deliver multiple open circuits on a target, and complete return circuits back to the weapon through more than one gap between the projectiles, which will significantly increase the weapon's power consumption and reduce its battery life circle. Still, the maximum effectiveness of this configuration depends on all projectiles impact on the target, and if all projectiles do impact on a target, the maximum effectiveness would be just as much as if only the projectile on the highest point and the one on the lowest impacted on the target with the longest gap; while if one or both projectiles, which is normally the lowest ones, miss the target, its advantage would be lost. In such case, only the two electric opposed projectiles on the upper side have the effective power while the ones below become useless.
The conventional weapons launch one projectile along the horizontal plane of the cartridge in order to provide guidance to the weapon's laser targeting mechanism, while the other projectile is launched at an angle downward. The latter increases the angular spreading effects and its downward velocity greatly increases its descent due to the gravitational force, which is one of the main causes for limited effective long shooting range. In addition, weapons disclosed in the prior art require that they must be held straight in order for the two projectiles to be arranged in the vertical direction to achieve the desired result, since turning the weapon at all will further increase the risk of causing the projectiles to miss the target. In addition, the projectile on the upper side is normally targeted at the center of the chest of a human body and there is a risk that its hooked sharp head will cause serious injuries to important organs such as eyes, throat, cervical artery and nerve in case of panic or other mistakes. It is desirable to lower this targeting point by a few inches to minimize the risk of said injuries.